Well, Mackem, apparently there's Kabuto near Newcastle's Civic Centre and Charmander at Leazes Park, so that's Saturday morning sorted for us, once DS1's done his Christmas shopping :o
We catch the 20/20A through quite regularly - that's the bus we took to Cleadon park, too, the other week. It also passes Broomside park in Durham, so it's a good Poketourist bus! The run through Houghton sometimes throws up some good pokemon, too.
Iwas if your phone's not locked, it'll probably be cheaper to walk into a Three store and pick up a PAYG SIM plus a tenner worth of credit (a fiver would be plenty, since it's 1p per MB, but you can't buy less than a tenner's worth in a shop - you can, however, top it up online with a credit card for just a fiver's worth) Will be handy if you need to phone for a takeaway or something, too, as calls are just 3p per minute.
In the time I've been playing Pokemon Go, since July, I've used up 1GB of Data on it, which isn't all that bad, really.